Three things all cyclists and motorists should do

I firmly believe that bikes are fundamentally different modes of transportation than driving or walking. I think it's unfortunate that bikes are, for the most part, treated by the law as "little cars." I recognize that this treatment has a long history. Given the amount of time which has passed since bikes were last the dominant conveyance on our streets, it's not surprising that streets were largely designed with cars in mind. Still, from my perspective, there are at least a few important ways that moving around by bike is much different than moving around in a car or truck:

1. Cyclists can safely get much closer to intersections (and see much better around corners) before committing to stop or go.
2. When cyclists put themselves in any sort of traffic situation, they are completely unprotected. For that reason alone, they will (if they have their thinking caps on) be much more cautious about risking an incident involving a car, bike or pedestrian.

Accordingly, I have no problem with people rolling through four-way stops or proceeding through a red light after stopping (even cars, assuming they are doing it right, but that's a whole 'nuther kettle of fish). Still, those things don't remove your obligation from being a good citizen on the road. Most of my riding is done in an urban environment, which colors my view of how things work. I realize that in lower density suburban and rural areas things may work differently. That said, I think the entire system would work much better if cyclists and motorists all considered these three points.

1. Never deny someone else their right-of-way. If you come to a four-way stop and someone else has already gotten there, that person (driver, pedestrian, cyclist) has the right-of-way. It's their choice to yield it or not, not yours. Don't take it from them.
2. Always signal your intentions. Many people seem to think that turn signals are optional. They are not. Ignoring the codified laws (which seem not to be enforced anyway), signaling your intention to turn, change lanes, or stop reduces confusion, and thus the risk of an incident.
3. Never accelerate to make a yellow light for which you can stop. No matter how experienced or lucky you are, eventually your experience will fail you and your luck will run out. You will run a red light, and collide with someone going the other way.

Note that I used the absolute words "never" and "always" above. I realize people make mistakes, and that perfection is impossible. Still, it should be a goal. Some days, I try and count the number of mistakes on my commute. I think it's a useful exercise. If you're honest about it, it might help you see your actions as they appear to other people.

There will be times when you fail to notice a light changing until it's too late to stop. As a cyclist, I know when I'm looking to see what hazards await me, I am much more finely tuned to motor vehicles. That means I will sometimes fail to see a pedestrian. That's a mistake. I need to get better at seeing everyone, not just the people who can do me the most harm. I also admit to not being the best person when it comes to signaling turns or stops when riding my bike. I will try to to better at that. For people in cars, you have no excuse. Your stop lights better work. If you fail to engage your turn signal (or, perhaps worse, set it, then change your mind and go straight), that's your fault, not mine.